Preparation of Stable Closo- and Nido-Cobaltaboranes from Na(+)B5H8(-). Complexes of the Formal B4H8(2-) and B4H8(2) and B4H6(4-) Ligands.
Abstract
The novel air-stable, crystalline metalloboranes nido-B4H8Co(pi-C5H5) (Ia), closo-R-1,2-B4H5Co2(pi-C5H5)2 (II, R=H; III, R = 3-cyclo-C5H9; IV, R = 4-cyclo-C5H9), and nido-5-B9H13Co(pi-C5H5) (V) have been prepared by the reaction of Na(+)B5H8(-) with CoCl2 and NaC5H5 in tetrahydrofuran solution followed by treatement with aqueous HCl and air oxidation. Pyrolysis of Ia with acetylene in the gas phase at 200 gives an isomer, Ib. From 11B and H nmr, infrared, and mass spectra it is proposed that the cage framework in Ia and Ib is a square pyramid analogous to B5H9 with cobalt occupying a basal position in Ia and an apex position in Ib, II-IV are closed octahedra analogous to C2B4H8, and V has a B10H14-like open-cage structure. All of the structures except Ib are proposed to contain B-H-Co bridging groups. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1973
- Accession Number
- AD0761642
Entities
People
- Russell N. Grimes
- Vernon R. Miller
Organizations
- University of Virginia